It is known in the art pertaining to automotive V-type internal combustion engines to provide an integral cylinder block having a pair of outwardly angled cylinder banks with inside walls defining a valley. In some engines the valley has been closed by an integral cast-in-place wall. In other engines, the valley may be upwardly open and may be closed by the mounting of an engine intake manifold or other member thereon to prevent the escape or contamination of engine oil or oil mist often existing within the valley.
Also, in the past, the cast iron or aluminum intake manifolds of V-type engines generally added to the stiffness of the cylinder block and head assembly by interconnecting the inner walls of the cylinder heads mounted on the cylinder banks. However, with the increasing use of molded plastic intake manifolds, the capability of intake manifolds to provide substantial stiffening of the block assembly is substantially lessened.